Optimizing decoding for laptop battery life

[fibbingbear]

I occasionally use my laptop on long flights to watch movies. I have a moderate amount of hard drive space (techincally enough to store a moderate number of ISOs, but I'd rather re-compress them and store more movies on there). I'd like to optimize the decoding for battery life (I don't care about encoding, since I can do that on my home machine beforehand).

I was wondering if anyone has any personal experiences with these. It's my understanding that the MPEG4-ASP have much lower decoding requirements than MPEG4-AVC, which I assume translates into longer battery life (less CPU used). Likewise, I've heard that using MP3 audio is better than OGG, again because it's a simpler algorithm so it takes less computational power to decode.

If people can post their thoughts (or if they have actual experiences with how it affects battery life, even better!), it'd be appreciated.

[saint-francis]

What kind of GPU does your laptop have? If it supports DXVA then x264 is the way to go. My tests with a kill-a-watt (http://www.p3international.com/products/special/P4400/P4400-CE.html) meter shows me that decoding h.264 with DXVA uses less energy than software decoding of xvid.

[fibbingbear]

I have some sort of ATI mobile processor. I did a dxdiag test and it seems like I have DXVA support. Are there any parameters in h.264 encoding that should be avoided to maximize battery life?

[saint-francis]

Are there any parameters in h.264 encoding that should be avoided to maximize battery life?

Anything that breaks DXVA. Other than that the difference between any settings is negligible. If you are going to be watching movies on a plane or some other noisy form of transportation you might want to check out well insulated noise canceling headphones. They will allow you to have better sound while keeping the volume much lower, thus saving power.